CVE-2026-8809
| Summary |
The Advanced Custom Fields: Extended plugin for WordPress is vulnerable to Privilege Escalation via Validation Bypass in all versions up to and including 0.9.2.5. The vulnerability exists due to the after_validate_save_post() function unconditionally trusting the attacker-controlled _acf_post_id POST parameter — with no authentication or integrity verification — to select a cleanup branch that silently discards all validation errors not prefixed with acfe:. This makes it possible for unauthenticated attackers to suppress both the role allow-list validation error added by acfe_field_user_roles::validate_front_value() and the administrator-role capability guard error added by acfe_module_form_action_user::validate_action(), causing wp_insert_user() to execute with an attacker-supplied administrator role argument and resulting in the creation of a new administrator-level user account. Exploitation requires the target site to expose a public ACFE frontend form configured with a Create User action that maps a role field.
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| Publication Date |
May 29, 2026, 8:16 a.m. |
| Registration Date |
May 30, 2026, 4:11 a.m. |
| Last Update |
May 29, 2026, 11:40 a.m. |
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CVSS3.1 : CRITICAL
|
| スコア |
9.8
|
| Vector |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| 攻撃元区分(AV) |
ネットワーク |
| 攻撃条件の複雑さ(AC) |
低 |
| 攻撃に必要な特権レベル(PR) |
不要 |
| 利用者の関与(UI) |
不要 |
| 影響の想定範囲(S) |
変更なし |
| 機密性への影響(C) |
高 |
| 完全性への影響(I) |
高 |
| 可用性への影響(A) |
高 |
Related information, measures and tools
Common Vulnerabilities List